1. Technical Field
The present invention relates to a door hinge for opening and closing a door of a domestic appliance, in particular an oven, comprising a hinge arm, a hinge lever pivotally fixed to the hinge arm and biasing means for biasing the door hinge in its closed position, wherein a locking device is provided for locking the door hinge in a predetermined opening position. Moreover, the present invention relates to an oven comprising a housing and a door, which is fixed to the housing by means of such door hinges.
2. Description of Related Art
Door hinges of the above mentioned kind are known in prior art. They are particularly used for the assembly of oven doors. During the assembly process the hinge arms of normally two door hinges are initially fixed to the oven housing. Then the oven door is fastened to the hinge levers of the door hinges, whereupon the oven door can be pivotally opened and closed by a user. In order to ensure a proper closing of the door, each door hinge is provided with biasing means for biasing the door hinge or rather the oven door in its closed position.
Moreover, ovens are known whose doors can be disassembled by a user in order to simplify the cleaning of the oven. Such ovens normally comprise a locking device for locking each door hinge in a predetermined opening position in order to prevent a snapping back of the hinge levers towards the closed position. This is because it is very difficult for the user to manually return the hinge levers against the force of the biasing means when re-assembling the oven door.
An oven having such locking devices is disclosed in DE-A-6 943 499. The oven comprises a housing and a door, which is fixed to the housing by means of two door hinges. Each door hinge has a hinge arm, which is fixed to the housing, and a hinge lever to which the oven door is attached. Moreover, each door hinge is provided with a snap-fitting plate, whose first free end is guided within a longish slit formed in the hinge lever and whose other free end is operatively connected to a spring, which biases the hinge lever along with the snap-fitting plate in the closed position of the door hinge. As soon as the oven door is moved upwards along the hinge levers during the disassembly of the door, the snap-fitting plates can be pivoted and locked under the influence of the springs. To do so, the door firstly needs to be moved in its predetermined opening position. Thereafter, it is drawn upwards a little bit and then tilted in order to turn and lock the snap-fitting plates of the door hinges. Afterwards the door can be removed from the hinge levers, which rest in the predetermined opening position.
One drawback of the door hinge disclosed in DE-A-6 943 499 is that the structure of the locking device is quite complex and thus expensive. Moreover, the locking device needs a lot of installation room. Furthermore, the user needs knowledge about how to manipulate the locking device, because the manipulation is not apparent from its outer appearance.